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FINGER TRAININGMy 8-year-old niece went for her first guitar lesson recently, and her music teacher suggested an exercise in which she was to lay her hands palm down on a flat surface and wiggle each finger in turn. When I tried it, I found that my ring finger on both hands was much less able than any of my other digits; I could barely lift it off the surface, let alone wiggle. When I put my knuckles on the surface in the form of a fist and extended each finger in turn, the ring finger was the only one I could not lift from the surface at all. Why is this? Presumably if I’m ever tortured and about to lose a finger, I should request that it be my ring finger…
● The human hand is an extremely
complicated bit of machinery.
Extension of a single digit requires the
simultaneous contraction of the
extensor muscle for the appropriate
digit, the relaxation of the flexors for
that digit and the contraction of the
flexors for all of the other digits – to
make them stay put. This happens
fairly easily in the thumb, index and
small fingers, as they all have their
own designated extensor muscles.
Extension in the middle and ring
fingers uses the common extensor
muscle, which supplies extension to
all fingers except the thumb. When
attempting to extend the ring finger,
the middle finger flexor contracts,
effectively “pinning down” the
middle finger, which the common
extensor then pulls against to no
avail. Try lifting the middle and fourth
finger as a unit and see how easy this
becomes when the middle finger
flexor no longer acts as a tether.
Some people have aberrant
connections between tendons and
others have extensors dedicated to
the ring finger , but the third and ring
finger linkage is almost universal.
Steve Ballinger
Nacogdoches, Texas, US
● The hand evolved primarily for
grasping, so playing a musical
instrument can push its design
specifications to the limit. I have a
particular interest in this as I run a
course on the biology of musical
performance at Cardiff University.
Music teachers need to be aware of
the high incidence of variability in the
muscles and tendons of the hand. As
a result, not everyone can make the
same finger movements. For example,
in about 20 per cent of hands, curling
up the thumb causes the index finger
to bend because of an anomalous link
between flexor tendons. This renders
some piano fingerings impossible and
barring on the guitar more difficult.
Alan Watson
Cardiff, UK
● I’m a touch-typist with a top speed
of 60 words per minute. I have typed
five days a week, for the past 25 years.
Over this time, I’ve developed quite
flexible fingers. I had no difficulty with
the exercises your correspondent
spoke of: all fingers were capable of
wiggling independently. I asked
another touch-typist to try the same.
She had no problems in lifting both
ring fingers and moving them
independently of the others either.
However, when I asked my sister,
who has never typed, to try it, she
experienced a great deal of difficulty,
and could not lift the left ring finger at
all from the prone position.
My teenage daughter found her
most flexible digits to be both
thumbs, presumably because she
spends hours using them to send text
messages from her mobile phone.
Alison Venugoban
Ngunnawal, ACT, Australia
● The ring finger has the least
dexterity because it is used least. The
index finger is used for pointing, the
little finger is extended while drinking
tea and the middle finger is used
when driving. The ring finger is used
only once, shortly before marriage.
Conor Nugent
Alexandria, Virginia, US
DUAL BLOTIs it feasible for wind turbines to be placed on or next to electricity pylons? This would surely overcome the main objection of them spoiling the landscape. If not, why not?
● On purely aesthetic grounds neither
option would get rid of the objections.
At 100 metres tall, a 1.5-megawatt
wind turbine is over twice as high as
the standard UK national grid pylon.
The majority of pylons have been
located to avoid high winds, while
wind turbines need to be in areas of
prodigious wind. An inland low-
altitude wind turbine on a site with a
wind speed of at least 3 to 4 metres
per second 50 per cent of the time
would produce barely 20 per cent of
the output of a coastal site with wind
speeds of at least 5 to 6 metres per
second 50 per cent of the time.
Building next to pylons would not
make construction savings but adding
a turbine to a pylon would require a
costly total rebuild of the pylon.
Lawrie O’ Connor
Ossett, West Yorkshire, UK
● Pylons and cables would create
eddies and vortices that would reduce
the effectiveness of the turbines. The
blades, meanwhile, would create
turbulence that would affect the strain
on the pylons, increasing the chance
of the cables snapping. If a cable
snapped under high wind or heavy
snow, it could be caught in the blades.
Finally, in all disaster planning,
the worst case scenario is always
considered. In any terrorist attack or
plane crash, you would lose not only
your power generator, but a part of
the electrical distribution system.
Kevin Saxon
Edinburgh, UK
THIS WEEK’S QUESTIONAlarming microwaveIf we use our microwave oven for
longer than about 30 seconds, our
car’s alarm goes off. Why? The car is at
least 20 metres away through two
walls. The inside of the microwave is a
little corroded and the car has a
remote central locking/alarm system.
James Joyce
Southampton, UK
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“Most pylons are located to avoid high winds, while wind turbines need prodigious wind”
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